gecko-dev/layout/reftests/text/letter-spacing-nolig-1-ref.html

<style>
.a {
  font: 32px/2 Times;
}
.b {
  font: 32px/2 Times;
  letter-spacing: 1em;
}
</style>

<div class="a">office

<div class="b">off&zwnj;ice